By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Forum House Ad Zone

What is EN24 like to machine?

All Topics | Latest Posts

Search for:  in Thread Title in  
Ian P13/01/2012 22:26:33
avatar
2747 forum posts
123 photos
I am contemplating turning and screwcutting a male thread 50mm diameter(pitch 3mm) on EN24 steel.
 
In the past I have screwcut small stuff mostly in non ferrous with no problems, for this project I would get a carbide tip with the correct thread form but I am wondering what sort of finish I can expect and whether something like this is well within the capabilities of a 5" Boxford
 
I have not knowingly used EN24 before but have modified numerous HT bolts, are they a comparable grade?
 
Ian
Stub Mandrel13/01/2012 22:54:30
avatar
4318 forum posts
291 photos
1 articles
I've machined it but only a few times.
 
EN24T will be fine, but make sure it is 'T' or tempered, not in the hard condition.
 
Tools need to be sharp and take it easy and it machines better than silver steel.
 
Neil
John Stevenson13/01/2012 23:34:07
avatar
5068 forum posts
3 photos
Neil, I think you mean EN24M the M stands for machinable.
 
Ian it does machine nice, on carbide try to go as fast as possible and neat cutting oil.
 
John S.
JohnF13/01/2012 23:51:48
avatar
1243 forum posts
202 photos
Ian, I use EN24T quite a bit but in smaller sizes, it machine's easily and you should have no trouble with screw cutting it and its well within you lathes capacity. I have cut threads 2 inch dia on my Myford S7.
 
With a fairly coarse thread 3mm, it might be wise to set the compound slide to 30 deg even though you are proposing to use a full form tip. Take a very small straight cut a the end with the cross slide to get the full form.
 
Regards John
GoCreate14/01/2012 00:37:56
avatar
387 forum posts
119 photos
Ian
 
For En 24 the added suffix indicates the material heat treated condition.
 
En24 'T' condition is hardened and tempered and quite tough to machine, in my experience it's a case of reduced speed, small depth of cut and adequate feedrate when using a light machine. Carbide tools are best, you can go to high speed very fine cuts and feeds for finishing however I find good finish is relatively easy to obtain at slower speeds and plenty cutting oil.
 
In 'T' condition Its tensile strength and hardness are in the range of grade 8.8 to 10.9 high tensile bolts. Most high tensile bolts will be either one of these grades, socket head cap screws are generaly of a higher 12.9 grade.
 
If you have been machining high tensile bolts then EN24T wil be similar.
 
En24 is commonly available in annealled conditon (M???) and heat treated 'T' condition.
 
As John S indicates, 'M' condition is easier to machine than high tensile grade 8.8/10.9 bolts.
 
Nigel

Edited By tractionengine42 on 14/01/2012 00:43:32

Raymond Anderson14/01/2012 07:35:34
avatar
785 forum posts
152 photos
Ian,
EN 24 in the "T" condition is the easiest to machine as it has the lowest tensile strength of the other conditions,which are U , V , W , X , and Z. [ I have never heard of a M condition ] I get all my EN24T from my brothers employers and EN16T, and I love machining both types as the finish is super I find them [EN16T ,EN24T] to be very clean materials to work with. I can't comment on Depth of cut or feed rates as I don't know the machine involved.
Regards,
Raymond.
traction engine42,
I don't wish to appear argumentative but, EN24T is not hardened, it has the lowest hardness of all the conditions.
Regards,
Raymond.
Ian P14/01/2012 09:52:56
avatar
2747 forum posts
123 photos
Thanks to all that have replied. From what I have learnt I now have no trepidation in making the parts I want. Regardless of what conditions it may be available in, most of the ME suppliers sell EN24 as EN24T so that is what I will get.
 
I presume/hope that I will not need to subsequently heat treat it for this application which is, the threaded part of a classic car 'Knock on' (or centrelock) hub.
 
Ian
 
Raymond Anderson14/01/2012 10:45:32
avatar
785 forum posts
152 photos
Ian,
You are correct in that model engineer suppliers usually stock in in the "T" condition as that is the most readily machinable grade. So have no fears with it, just be sensible with your depth of cut and feed rates and you will have a steel that finishes just a treat.
Also, if you plan on using it often, then the following inserts "WALTER, WPP01" have a very good tool life.
Regards,
Raymond.
Steve Withnell14/01/2012 11:10:45
avatar
858 forum posts
215 photos
I'm quite confused now. Is EN24T tempered and hardened or just tempered for machining before hardening?
 
I cannot find any references via Google to EN24M , though I can find an EN16MT which has a better machinability index (39%) than EN16T and EN16T has the same machinability index as EN24T (29%).
 
I find I can get a really good finish on the EN16T I've played with, provided I go hell for leather with neat cutting oil (it's the only cutting oil I have), but this makes taking short cuts (say 4mm as a slot in a bar 10mm deep) to close tolerances and getting an immaculate finish a really big challenge.
 
Steve
 
 
GoCreate14/01/2012 11:59:25
avatar
387 forum posts
119 photos
Hi Raymond
Other than in the annealed condition En24T is the easiest to machine in the range T to Z.
All the conditions T to Z are hardened, they are given different tempers to achive different mechanical properties, T condition has the highest temper and therefore the easiest in this range to machine
 
I have not heard of En 24 M,
 
I have used En8M which is great to machine but is a lower strength material.
 
Nigel
Raymond Anderson14/01/2012 14:45:38
avatar
785 forum posts
152 photos
Nigel,
Sorry about the confusion on my part, I thought you meant that the EN24T was
" Hardened" as in "you need CBN to machine it" so my apologies.
When I asked the brother about EN24M ?? he had never heard of it and he uses the 24 almost every day, and when he's not using the 16/24, it is another powder puff material Inconel 718
Yes, EN8 M or DM is nice stuff although I don't get so much of it.
Regards,
Raymond.
rakesh bhargava23/02/2012 17:26:11
1 forum posts

Hello Raymond,

I am new to EN24 and Heat Treatments. I need to heat treat EN24 to Z condition. Can you tell me how is Z treatment done? What is the meaning of U V W X and Z Heat Treatments?

Regards,

Rakesh Bhargava

GoCreate23/02/2012 17:48:22
avatar
387 forum posts
119 photos

Hi Rakesh

Here is some info on heat traeted conditions of EN24.

Can't realy give any specific help with heat traetement but I guess you will heat to cherry red, soak at that temp for a while, quench in oil, temper to a light purple. This might help.

444HB converts to 48 RC

Nigel

M0BND23/02/2012 23:31:01
81 forum posts
9 photos

817M40T - EN24T. Quite a tough form of steel, however, don't be afraid of it! It's lovely to machine, you won't get a perfect finish (maybe 0.8 or N6 surface finish) but with correct speeds and feeds, you will be very pleased with the results you get!!!

Have a look at http://www.steelexpress.co.uk/engineeringsteel/EN24.html

Andy.

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Sign up to our Newsletter

Sign up to our newsletter and get a free digital issue.

You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy

Latest Forum Posts
Support Our Partners
cowells
Sarik
MERIDIENNE EXHIBITIONS LTD
Shopping Partners
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest

 

Donate

donate